Valve and sprinkler head for automatic fire extinguishing systems

ABSTRACT

A sprinkler head with an associated heat responsive actuator is replaceably coupled to an on-off valve, positioned intermediate the source of fire extinguishing fluid and sprinkler head. The on-off valve which is normally closed is opened by an associated heat responsive actuator and spring-closed when the temperature falls below the preselected temperature.

Dec. 9, 1975 United States Patent [191 Groos 3,757,866 9/1973 Mears et a1. 3 759 331 9/1973 Livingston VALVE AND SPRINKLER HEAD FOR AUTOMATIC FIRE EXTINGUISHING SYSTEMS Inventor:

3,791,450 2/1974 Poitras.......... 3,797,746 3/1974 3,802,510 4/1974 m tn w n h 0 GJ [75] Richard T. Groos, Hastings, Mich.

[73] Assignee: The Viking Corporation, Hastings,

Primary ExaminerRobert S. Ward, Jr. Assistant Examiner-Michael Mar Mich.

Attorney, Agent, or FirmPrice, Heneveld, Huizenga & Cooper [22] Filed: Feb. 20, 1974 [21] Appl. No.: 443,962

[57] ABSTRACT A sprinkler head with an associated heat responsive actuator is replaceably coupled to an on-off valve, positioned intermediate the source of fire extinguishing fluid and sprinkler head. The on-off valve which is normally closed is opened by an associated heat responsive actuator and spring-closed when the temperature falls below the preselected temperature.

25 Claims, 3 Drawing Figures [52] US Cl 169/19; 169/37; 251/301 [51] Int. A62C 37/10 [58] Field Of Search............... 169/5, 19, 37, 90, 20; 251/301 [56] References Cited UNITED STATES PATENTS 3,685,588 8/1972 Livingston 169/37 3 734191 5/1973 Johnson et 169/5 w 1 I/1%- e d H US. Patent Dec. 9, 1975 VALVE AND SPRINKLER HEAD FOR AUTOMATIC FIRE EXTINGUISHING SYSTEMS BACKGROUND Conventional sprinkler heads are in general use today. They employ a plug of fusible link material which, when subjected to temperatures above a predetermined level, melts and causes the plug to be removed permitting water or other fire quenching fluid to escape and douse the fire. The operation destroys the plug, and the head continues to spew forth fluid even after the temperature or fire source has subsided. If the fire occurs in the absence of personnel, extensive damage can be experienced by the continual emission of extinguishing fluid long after the fire has been terminated. In other cases, even where personnel are present, the system may be turned off to terminate excessive flow and unbeknownst to the personnel, the actual causation of the fire has not been completely kindled. Reflaming however will not be counteracted by the system since it is turned off. Yet another disadvantage is the requirement that the system be turned off while replacing heads which have been activated. Failure to turn the system back on has been experienced and unbeknownst to the user, years can expire with no meaningful protection whereupon there is no supply in response to a demand.

There has been recent activity in this art and one suggested solution has been to replace the sprinkler head with an on-off valve which in theory is opened when the temperature reaches a preselected level and is closed when it drops below that level. In this fashion, when the heat reaches a preselected temperature, the sprinkler system is activated and when it drops below that level it is shut off. Subsequent rekindling will cause it to open once more. Several disadvantages have been experienced by this type of on-off valve system. A major drawback is the requirement in this art that a particular system be operational for a period of years. It is not uncommon that a system might be in existence for -40 years without ever being utilized. It must, however, be operational after that length of time. Current on-off valve proposals appear to meet the longevity requirement in that they will be turned on after this length of time. but present valve art does not permit any insurance that after the temperature has been reduced below the preselected level that the valves will seat securely. Hence, there is a high probability that water will continue to flow requiring that the system be shut off and the on-off valve replaced.

The utilization of on-off valves creates other problems as well. Existing disadvantages are the lack of real flexibility. Current on-off valves known to Applicant can be used as a pendant sprinkler head but not as an upright. Current valves also have no interchangeability of the heat responsive mechanism such that where a different temperature level is desired, completely different heads must be installed. Further, the known onoff valves operate between a completely open and completely closed position. Thus, regardless of the magnitude of the heat source, maximum fluid is dispensed. This in many cases can cause damage exceeding that caused by the particular heat source. The heat responsive sensor itself is also subject to being prematurely cooled in a fire situation by the fluid such that the valve could be turned off before the heat source is extinguished. Thus, there is a significant need in this art for an improved automatic fire extinguishing system.

SUMMARY OF THE INVENTION In accordance with the invention, a fluid passageway is formed in a valve body means, the passageway having an inlet adapted for connection to a fire extinguishing fluid source, the outlet being positioned to dispense the fluid under preselected conditions. A pair of normally closed valve means are positioned in the flow passageway. A first condition responsive actuator causes the first valve means to become unseated when a preselected condition level is reached and means are provided to close the first valve means when the condition level is below a preselected level. A second condition responsive actuator causes unseating of the second valve means at a second preselected condition level which may or may not coincide with the first preselected condition level. The first valve is connected to a fire extinguishing fluid source and a deflector is provided at the outlet of the second valve body to distribute fluid flow established therethrough.

Preferably, the condition level is temperature and the first valve means is an on-off valve actuated by wax motor utilizing a piston drive to move the valve off its seat. One or more springs are utilized which have a spring force sufficient to overcome the force of the wax motor when the temperature drops below a preselected level to reseat the valve. The second valve means is preferably a sprinkler head removably interconnected to the on-off valve. The sprinkler head preferably employs a plug of fusible material which when subjected to temperatures above a predetermined level melts and opens the head permitting water or other fire quenching fluid to escape and-douse the fire. The two related heat responsive actuators may or may not be set for actuation at the same temperature level depending on the design criteria. For example, a lower ambient heat may be selected to cause the on-off valve to be opened prior to the opening of the sprinkler head such that the system at various points is charged prior to actual utilization. Another alternative would be to lock the on-off valve open until the sprinkler head is actuated and provide for closing of the valve after the temperature drops once again. The system may be utilized in a dry or wet system and the sensors can be positioned remotely from the actual mechanisms to prevent premature shut off. The control responsive actuator can be responsive to a variety of fire related ingredients such as a preselected fixed temperature level (preferred), rate of temperature change, smoke density, pressure, radiation etc. The wax motor is replaceable to permit complete flexibility in selecting the arbitrary temperature level at which the system will dispense fluid. If with the course of time, the first valve means does not completely reseat after opening, it will at least reduce the amount of flow to a dribble which is not destructive. The system is completely rehabilitated then by simply replacing the conventional sprinkler head which does not even require that the actual fluid pressure source be turned off.

The unique combination of an on-off valve with a sprinkler head provides a system utilizing the particular advantages of each type of mechanism eliminating their individual drawbacks. Thus, it solves the problem of heat cycling and long range resistance to leakage. In addition, the combination provides additional advantages in flexibility not heretofore present in this art.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view in cross section of the combined on-off valve and sprinkler head of my invention;

FIG. 2 is a plan view of the on-off valve in the closed position with the cover removed; and

FIG. 3 is a view similar to FIG. 1 with the valve opened.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings in detail FIG. 1 illustrates the improved valve and sprinkler head comprising an on-off valve 12 coupled to a sprinkling head valve 14 by a coupler 16. The inlet 18 to the on-off valve'12 is connected to a source of fire extinguishing fluid (not shown) and when both valves are opened, fluid is dispensed through the outlet 20 of the sprinkler head and directed against a deflector 22 for distribution over the fire or other heat source.

The on-off valve 12 is comprised of a valve body 24 which includes a cover 26 removably fastened thereto by a plurality of arcuately spaced set screws or the like (not shown) threadable into openings 28. A flow passageway 30 extends through the valve body having an inlet 18 and an outlet 32.

An enlarged chamber 34 is formed within passageway 30. The transition 36 between chamber 34 and the outlet portion 32 of passageway 30 forms a valve seat. Seat 36 includes an annular seat portion 38 formed of a plastic or rubber material such as Delrin. The valve itself is comprised of a pivot arm 40 pivotal about a post 42, the valve element 44 comprising a disc movable between a closed position (FIG. 2) over sealing element 38 to various open positions (FIG. 3) to permit flow through passageway 30. The back side of disc 44 includes a centrally located post 46 loosely positioned through an' opening 48 formed through arm 40. Valve 44 is thus loosely secured to arm 40 and it will be appreciated that when it is positioned into seating engagement over seal element 38, the fluid pressure behind valve 44 causes it to seat firmly against seat element 38.

Referring specifically to FIGS. 2 and 3, the arcuate movement of arm 40 in the clockwise direction is limited by a stop post 50. A threaded post 52 extends from the side of arm 40 and is adapted for engagement with stop 50. The axial extension of threaded post 52 from arm 40 is adjustable to permit adjustment in the degree of arcuate rotation of arm 40 in the clockwise direction. A pair of springs 54 and 56 operate to urge arm 40 and associated valve element 44 to their maximum clockwise rotational position. In this position, the valve is completely closed effectively shutting off all flow through on-off valve 12. Except for any leakage, flow is also shut off through sprinkler head 14 even if it were open.

Spring 54 is a coil spring wrapped around post 58, one end 60 of the spring bears against the inner wall of housing 24 and the other end 62 is biased against a post 64 anchored near the other end of arm 40. Spring 56 is likwise a coil type spring wrapped around post 42 having one end 66 biased against the inner wall of housing 24 and the other end 68 biased against a wall 70 formed near the inner end of arm 40. Arm 40 has a stepped cross section (FIG. 1) with the lower inner end 72 offset from the upper outer end 74. The step portion forms wall 70. The utilization of two separate springs 54 and 56 provides a constant bias force against counterclockwise rotation of arm 40 regardless of whether it is positioned near its maximum clockwise (closed) rotational position or its maximum counterclockwise rotational (open) position. It will be appreciated that depending on the particular design characteristics and the pressures involved, a single spring or other type of bias means could be utilized. The maximum degree of counterclockwise rotation of valve arm 40 is reached when the periphery of valve disc 44 abuts against the inner wall of housing 24. It will be appreciated that in this position, the influence of spring 56 is maximized whereas the influence of spring 54 is diminished significantly since the direction of force generation is toward post 42 instead of in a pivotal direction thereabout.

The opening of on-off valve 12 is achieved by the counterclockwise rotation of arm 40 from the position illustrated in FIGS. 1 and 2. In the preferred embodiment, this is achieved by a wax motor 80 which includes a heat sensor 82, a piston body 84 inserted through the wall of housing 24 having a piston 86 extending beyond the inner wall of housing 24 into abutment with a seat 88 formed in the side of valve arm 40. Seat 88 is sloped or tapered relative the end of piston 86 to facilitate rotational moving engagement between piston 86 and arm 40.

The operation of wax motors are well known and it will be appreciated that depending on the design criteria, when the temperature surrounding sensor 82 reaches a predetermined level, the wax expands forcing piston 86 outwardly causing valve arm 40 to unseat valve disc 44. Depending on the rate of temperature rise and temperature reached, the arm can be urged completely to its maximum counterclockwise position totally unseating valve disc 44 or an intermediate open position as illustrated in FIG. 3. If the source of temperature is insufficient to reach certain preselected levels, the flow through passageway 30 can be limited by the degree of unseating of valve disc 44. When the temperature recedes below a preselected level, the wax within wax motor will contract allowing the spring forces of springs 54 and 56 to operate on valve arm 40 to overcome the pressure against piston 86 permitting valve disc 44 to reseat.

Wax motor 80 is threaded into valve housing 24 and it will be appreciated that it can be quickly replaced with a similar motor having different temperature performances. Thus, on-off valve 12 is extremely flexible in that it can be utilized in a variety of systems with different design demands without having to change the entire valve structure.

Referring specifically to FIG. 1, sprinkler head 14 is connected to on-off valve 12 downstream of the fluid source (not shown). A coupler 16 is preferably utilized to space sprinkler head 14 sufficiently from on-off valve 12 for better fluid distribution during operation. This also reduces any tendency for fluid dispensed through sprinkler head 14 to immediately cool wax motor 80 which might cause premature shut off of valve 12. While it is normally not desirable to spray water on the valve actuating mechanism 80, there might be cases where this is desirable.

Sprinkler head valve 14 includes a valve body 90 having a flow passageway 92 with an inlet 94 connected to coupler I6 and an outlet 96. The plug 98 is seated over the outlet 96, there being a sealing element 100 squeezed between the plug and valve body to insure against leaking. A deflector 22 is spaced from outlet 96 and axially aligned therewith to distribute fluid through outlet 96 evenly over a defined area. Deflector 22 is integral with sprinkler head body 90 there being a support arm 102 interconnecting the two.

In the particular embodiment illustrated, a pair of tensioning arms 104 and 106 create a leverage between a seat 108 on deflector 22 and a seat 110 formed in the outer surface of plug 98. The two arms 104 and 106 are in levered engagement at 1 l2 and held in levering position by a pair of offset discs 114 and 116 held together by a fuse element 120. Each of the discs 114 and 116 have a pair of aligned apertures 122, 122a and 124, 124a through which the outer portion of arms 104 and 106 seat. A load is exerted on arms 104, 106 which through the leverage of arms 104 and 106 causes an increased load against plug 98. This insures proper seating against any water pressure exerted against plug 98. Fuse 120 is designed to deteriorate at a preselected temperature causing arms 104 and 106 to spring outward from each other releasing plug 108. As soon as this occurs, free flow through sprinkler head 90 is permitted. As in most conventional sprinkler heads, once the head is activated, it must be replaced after use. The sprinkler head and its operation is not described in complete detail since it is conventional in this art and a variety of different types of sprinkler heads could be utilized in combination with the on-off valve to provide the advantages of this system. Different on-off valves than the one described above could be used also including the use of a pilot valve.

There are particular instances where a phenomenon known as cold soldering can occur utilizing sprinkler heads of the type illustrated in FIG. 1. This phenomenon can occur with all types of sprinkler heads. If the sprinkler heads are positioned in particular close proximity to each other, two sprinkler heads might be activated by a heat source almost simultaneously. As the temperature rises fuse 120 begins deteriorating and offset discs 114 and 116 will move relative each other permitting corresponding movement of arms 104 and 106 before total displacement causing plug 98 to become unseated slightly. This transitional movement or unseating can last for a period of 5 to 30 seconds depending on the rate of temperature rise. There are occasions wherein two adjacent sprinkler heads are activated at the same time and the spray ejecting from each cools the adjacent fuse during this transitional movement causing cold soldering with both sprinkler heads then leaking. If the temperature source persists, the fuse completely deteriorates and the sprinkler will operate as designed. There are occasions, however, when this does not occur and damage can accrue from continual leakage through the sprinkler heads. This could be completely avoided by selecting a fusing temperature for the sprinkler head of less magnitude than the on-off valve whereby the sprinkler heads are activated first. On the other hand, the valve and sprinkler head can be arranged to actuate simultaneously or with the on-off valve being changed first. The significance of the unique combination is the complete flexibility of the system.

The valve is designed to be mounted in any position. Because there is no need to have a tight seal in the cycling valve, the valve will be self-draining when the sprinkler is pointed upward. This is an important consideration in dry sprinkler systems which are subject to freezing. Furthermore, the phsyical relationship between the valve actuating mechanism and the sprinkling actuating mechanism is in a sense infinite. They can be positioned very close together or very far apart.

.Indeed, conceivably, they could be one and the same element. Further, the heat responsive portion of the actuating mechanism could be positioned remotely from the sprinkler or valve to completely insulate it from premature shut-off when the sprinkler is on.

Having described the preferred on-off valve and sprinkler head combination in detail, the particular operation should be obvious. Assuming that the on-off valve actuator mechanism is set for actuation at a lower temperature than the sprinkler head, the increasing heat of a fire would open the valve to the sprinkler. However, no water would flow. When the sprinkler operated however, the water would flow through the valve and then through the sprinkler onto the fire. As the temperature decreased, the valve actuator would close the valve. In the event there had been an extensive time lapse between the installation of the valve and its actuation, it is conceivable that a small amount of leakage might occur. This however would not be nearly so destructive as the case in existing installations wherein the system operates at full force until it is shut down. Once the fire is extinguished however, the fused sprinkler head can easily be replaced with a new sprinkler without having to change the on-off valve even if it does leak since the new fused sprinkler will prevent all flow. As. a modification of the above principal, the valve could be locked open until the sprinkler head is fused. This would have the further advantage that the system would be fail-safe in that it would not be contingent upon the opening of the valve to obtain water and would also allow for drainage in the case of a dry sprinkler system. Thus, it will be appreciated that there exists a vast number of modifications within the framework of the unique combination which provides a very flexible system. Thus, although but one embodiment has been shown and described in detail, it will be obvious to those having ordinary skill in this art that the details of construction of this particular embodiment may be modified in a great many ways without departing from the unique concepts presented. It is therefore intended that the invention is limited only by the scope of the appended claims rather than by particular details of construction shown, except as specifically stated in the claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An automatic sprinkler control mechanism comprising, in combination: means defining a flow passageway having an inlet and outlet, said inlet adapted for connection to a source of fire extinguishing fluid, said outlet adapted to dispense said fluid; first and second valve means in said passageway, said first valve means being movable between closed and open positions, said second valve means being movable from a closed to an open position; first condition responsive means including first sensing means responsive to a fire condition and first actuator means responsive to said first sensing means and cooperatively associated with said first valve means for opening said first valve means when the fire condition about said first condition responsive means reaches a preselected fire condition level and for closing said first valve means when the fire condition level is below said preselected level; second condition responsive means including second sensing means responsive to a fire condition and second actuator means responsive to said second sensing means and cooperatively associated with said second valve means for caus ing said second valve means to open when the fire condition level about said second condition responsive means reaches a second preselected level.

2. The combination according to claim 1 wherein said first valve means is housed in a first valve housing and said second valve means is housed in a second valve housing, said second housing being removably connected to said first housing.

3. The combination according to claim 2 wherein said first condition responsive means includes a first portion which opens said first valve means and a second portion which closes said first valve means, said first portion being removably connected to said first valve housing and said second condition responsive means is cooperatively associated with said second valve housing and spaced from said first condition responsive means.

4. The combination according to claim 3 wherein said valve housings are spaced from each other by a coupler, said coupler forming a part of said passageway means.

5. The combination according to claim 3 wherein said first sensing means includes a condition sensor spaced from said first housing.

6. The combination according to claim 2 wherein said first valve means includes a valve seat in said first housing, a valve disc positionable over said seat closing said valve means, a valve arm rotatably anchored in said first valve housing, said disc being interconnected to said arm for movement therewith to a closed or opened position.

7. The combination according to claim 6 wherein said first condition responsive means includes a spring means positioned within said first housing and engageable with one of said arm and disc to urge said disc on said seat.

8. The combination according to claim 6 wherein said first actuator means includes a heat responsive wax motor removably mounted in said first valve housing, said wax motor having a piston extending into abutment with said arm, said wax motor including wax which expands when the ambient heat about said wax reaches a preselected temperature to force said piston outwardly causing said arm to move and unseat said disc.

9. The combination according to claim 8 wherein said first condition responsive means includes bias means urging said disc onto said seat, the force of said motor being sufficient to overcome said bias means when the said ambient temperature is greater than the said preselected temperature and the force of said bias means being great enough to overcome the force of said piston and move said arm and disc to their closed position when the said ambient temperature is below the said preselected temperature.

10. The combination according to claim 8 wherein said arm includes a cam face, the head of said piston being engageable with said cam face, movement of said piston causing movement of said piston head along said cam face to rotate said arm about an axis.

11. The combination according to claim 10 wherein said arm includes an aperture spaced from said axis, said disc including a post extending therefrom through said aperture whereby movement of said arm causes joint movement of said disc, said disc being free to move in a direction generally perpendicular to said arm wherebythe pressure of fluid from said fire extinguishing source causes said disc to seat evenly on said seat when said disc and arm are in said closed position.

12. The combination according to claim 11 wherein said first valve means includes a stop which limits the movement of said arm when urged in a closing direction to index said disc properly over said seat.

13. The combination according to claim 12 wherein said stop includes a post positioned in said housing and a pin means threaded into said arm and aligned for abutment with said post, said threaded pin providing adjustment of said stop.

14. The combination according to claim 1 wherein said first and second sensing means are heat responsive and said first and second preselected condition levels are temperature levels.

15. The combination according to claim 14 wherein said first preselected temperature level equals said second preselected temperature level.

16. The combination according to claim 14 wherein said first preselected temperature level is greater than said second preselected temperature level.

17. The combination according to claim 14 wherein said first preselected temperature level is less than said second preselected temperature level.

18. An automatic sprinkler control mechanism comprising, in combination: means defining a flow passageway having an inlet and outlet, said inlet adapted for connection to a source of fire extinguishing fluid, said outlet adapted to dispense said fluid; valve means in said passageway, said valve means being movable be tween open and closed positions; first condition responsive means including first sensing means responsive to a fire condition and first actuator means responsive to said first sensing means and cooperatively associated with said valve means to open said valve means when the fire condition about said first condition responsive means reaches a preselected level and urging said valve means to a closed position when the fire condition is below said preselected level; plug means spaced from said valve means closing said passageway; and second condition responsive means including second sensing means responsive to a fire condition and second actuator means responsive to said second sensing means and cooperatively associated with said plug means causing removal of said plug to open said passageway when the fire condition level about said second condition responsive means reaches a preselected level.

19. The combination according to claim 18 wherein said valve means is housed in a valve housing and said plug means is housed in a plug housing removably connected to said valve housing.

20. The combination according to claim 18 wherein said first and second sensing means are heat responsive.

21. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature below the temperature which causes said plug means to be removed.

22. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature above the temperature which causes said plug means to be removed.

23. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature equal to the tempemtum which Causes Said P means to be 25. The combination according to claim 18 wherein moved said valve means, plug means and flow passageway are 24. The combination according to claim 1 wherein h h d 1 means are removabl said first and second valve means and said flow pas- Ouse m a Ousmg an Sal p ug y sageway are housed in a housing and said second valve 5 Connected theretomeans is removably connected thereto. 

1. An automatic sprinkler control mechanism comprising, in combination: means defining a flow passageway having an inlet and outlet, said inlet adapted for connection to a source of fire extinguishing fluid, said outlet adapted to dispense said fluid; first and second valve means in said passageway, said first valve means being movable between closed and open positions, said second valve means being movable from a closed to an open position; first condition responsive means including first sensing means responsive to a fire condition and first actuator means responsive to said first sensing means and cooperatively associated with said first valve means for opening said first valve means when the fire condition about said first condition responsive means reaches a preselected fire condition level and for closing said first valve means when the fire condition level is below said preselected level; second condition responsive means including second sensing means responsive to a fire condition and second actuator means responsive to said second sensing means and cooperatively associated with said second valve means for causing said second valve means to open when the fire condition level about said second condition responsive means reaches a second preselected level.
 2. The combination according to claim 1 wherein said first valve means is housed in a first valve housing and said second valve means is housed in a second valve housing, said second housing being removably connected to said first housing.
 3. The combination according to claim 2 wherein said first condition responsive means includes a first portion which opens said first valve means and a second portion which closes said first valve means, said first portion being removably connected to said first valve housing and said second condition responsive means is cooperatively associated with said second valve housing and spaced from said first condition responsive means.
 4. The combination according to claim 3 wherein said valve housings are spaced from each other by a coupler, said coupler forming a part of said passageway means.
 5. The combination according to claim 3 wherein said first sensing means includes a condition sensor spaced from said first housing.
 6. The combination according to claim 2 wherein said first valve means includes a valve seat in said first housing, a valve disc positionable over said seat closing said valve means, a valve arm rotatably anchored in said first valve housing, said disc being interconnected to said arm for movement therewith to a closed or opened position.
 7. The combination according to claim 6 wherein said first condition responsive means includes a spring means positioned within said first housing and engageable with one of said arm and disc to urge said disc on said seat.
 8. The combination according to claim 6 wherein said first actuator means includes a heat responsive wax motor removably mounted in said first valve housing, said wax motoR having a piston extending into abutment with said arm, said wax motor including wax which expands when the ambient heat about said wax reaches a preselected temperature to force said piston outwardly causing said arm to move and unseat said disc.
 9. The combination according to claim 8 wherein said first condition responsive means includes bias means urging said disc onto said seat, the force of said motor being sufficient to overcome said bias means when the said ambient temperature is greater than the said preselected temperature and the force of said bias means being great enough to overcome the force of said piston and move said arm and disc to their closed position when the said ambient temperature is below the said preselected temperature.
 10. The combination according to claim 8 wherein said arm includes a cam face, the head of said piston being engageable with said cam face, movement of said piston causing movement of said piston head along said cam face to rotate said arm about an axis.
 11. The combination according to claim 10 wherein said arm includes an aperture spaced from said axis, said disc including a post extending therefrom through said aperture whereby movement of said arm causes joint movement of said disc, said disc being free to move in a direction generally perpendicular to said arm whereby the pressure of fluid from said fire extinguishing source causes said disc to seat evenly on said seat when said disc and arm are in said closed position.
 12. The combination according to claim 11 wherein said first valve means includes a stop which limits the movement of said arm when urged in a closing direction to index said disc properly over said seat.
 13. The combination according to claim 12 wherein said stop includes a post positioned in said housing and a pin means threaded into said arm and aligned for abutment with said post, said threaded pin providing adjustment of said stop.
 14. The combination according to claim 1 wherein said first and second sensing means are heat responsive and said first and second preselected condition levels are temperature levels.
 15. The combination according to claim 14 wherein said first preselected temperature level equals said second preselected temperature level.
 16. The combination according to claim 14 wherein said first preselected temperature level is greater than said second preselected temperature level.
 17. The combination according to claim 14 wherein said first preselected temperature level is less than said second preselected temperature level.
 18. An automatic sprinkler control mechanism comprising, in combination: means defining a flow passageway having an inlet and outlet, said inlet adapted for connection to a source of fire extinguishing fluid, said outlet adapted to dispense said fluid; valve means in said passageway, said valve means being movable between open and closed positions; first condition responsive means including first sensing means responsive to a fire condition and first actuator means responsive to said first sensing means and cooperatively associated with said valve means to open said valve means when the fire condition about said first condition responsive means reaches a preselected level and urging said valve means to a closed position when the fire condition is below said preselected level; plug means spaced from said valve means closing said passageway; and second condition responsive means including second sensing means responsive to a fire condition and second actuator means responsive to said second sensing means and cooperatively associated with said plug means causing removal of said plug to open said passageway when the fire condition level about said second condition responsive means reaches a preselected level.
 19. The combination according to claim 18 wherein said valve means is housed in a valve housing and said plug means is housed in a plug housing removably connected to said valve housing.
 20. The combination according to claim 18 wherein saId first and second sensing means are heat responsive.
 21. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature below the temperature which causes said plug means to be removed.
 22. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature above the temperature which causes said plug means to be removed.
 23. The combination according to claim 20 wherein said first heat responsive sensing means causes said valve means to be open at a temperature equal to the temperature which causes said plug means to be removed.
 24. The combination according to claim 1 wherein said first and second valve means and said flow passageway are housed in a housing and said second valve means is removably connected thereto.
 25. The combination according to claim 18 wherein said valve means, plug means and flow passageway are housed in a housing and said plug means are removably connected thereto. 